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A286106 a(1) = 0, and for n > 1, a(n) = A286105(A285735(n)) - A286105(A285734(n)).

%I A286106 #17 Apr 30 2021 06:05:55
%S A286106 0,0,1,0,1,0,2,1,1,0,0,0,1,0,1,1,0,0,2,0,0,0,1,1,1,0,0,0,0,0,0,0,1,0,
%T A286106 0,1,0,0,0,-1,-1,0,0,0,1,0,1,1,0,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,0,0,-1,
%U A286106 0,0,0,0,0,1,0,1,0,-1,0,0,1,0,0,-1,0,0,0,0,1,1,1,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
%N A286106 a(1) = 0, and for n > 1, a(n) = A286105(A285735(n)) - A286105(A285734(n)).
%H A286106 Antti Karttunen, <a href="/A286106/b286106.txt">Table of n, a(n) for n = 1..10000</a>
%F A286106 a(1) = 0, and for n > 1, a(n) = A286105(A285735(n)) - A286105(A285734(n)).
%o A286106 (Scheme) (define (A286106 n) (if (= 1 n) 0 (- (A286105 (A285735 n)) (A286105 (A285734 n)))))
%o A286106 (Python)
%o A286106 from sympy.ntheory.factor_ import core
%o A286106 def issquarefree(n): return core(n) == n
%o A286106 def a285734(n):
%o A286106     if n==1: return 0
%o A286106     j=n//2
%o A286106     while True:
%o A286106         if issquarefree(j) and issquarefree(n - j): return j
%o A286106         else: j-=1
%o A286106 def a285735(n): return n - a285734(n)
%o A286106 def a286105(n): return 0 if n==1 else 1 + max(a286105(a285734(n)), a286105(a285735(n)))
%o A286106 def a286106(n): return 0 if n==1 else a286105(a285735(n)) - a286105(a285734(n))
%o A286106 print([a286106(n) for n in range(1, 121)]) # _Indranil Ghosh_, May 02 2017
%Y A286106 Cf. A285734, A285735, A286105, A286107.
%K A286106 sign
%O A286106 1,7
%A A286106 _Antti Karttunen_, May 02 2017